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Upconverting stimulated emission depletion microscopy (U‐STED) is emerging as an effective approach for super‐resolution imaging due to its significantly low depletion power and its ability to surpass the limitations of the square‐root law and achieve higher resolution. Though the compelling performance, a trade‐off between the spatial resolution and imaging quality in U‐STED has been recognized in restricting the usability due to the low excitation power drove high depletion efficiency. Moreover, it is a burden to search for the right power relying on trial and error as the underpinning mechanism is unknown. Here, a method is proposed that can easily predict the ideal excitation power for high depletion efficiency with the assistance of the non‐saturate excitation based on the dynamic cross‐relaxation (CR) energy transfer of upconversion nanoparticles. This allows the authors to employ the rate equation model to simulate the populations of each relevant energy state of lanthanides and predict the ideal excitation power for high depletion efficiency. The authors demonstrate that the resolution of STED with the assistance of nonsaturated confocal super‐resolution results can easily achieve the highest resolution of sub‐40 nm, 1/24th of the excitation wavelengths. The finding on the CR effect provides opportunities for population control in realizing low‐power high‐resolution nanoscopy. [ABSTRACT FROM AUTHOR]

Preeclampsia is a heterogeneous and multiorgan cardiovascular disorder of pregnancy. Here, we report the development of a novel strip‐based lateral flow assay (LFA) using lanthanide‐doped upconversion nanoparticles conjugated to antibodies targeting two different biomarkers for detection of preeclampsia. We first measured circulating plasma FKBPL and CD44 protein concentrations from individuals with early‐onset preeclampsia (EOPE), using ELISA. We confirmed that the CD44/FKBPL ratio is reduced in EOPE with a good diagnostic potential. Using our rapid LFA prototypes, we achieved an improved lower limit of detection: 10 pg ml−1 for FKBPL and 15 pg ml−1 for CD44, which is more than one order lower than the standard ELISA method. Using clinical samples, a cut‐off value of 1.24 for CD44/FKBPL ratio provided positive predictive value of 100 % and the negative predictive value of 91 %. Our LFA shows promise as a rapid and highly sensitive point‐of‐care test for preeclampsia. [ABSTRACT FROM AUTHOR]

Preeclampsia is a heterogeneous and multiorgan cardiovascular disorder of pregnancy. Here, we report the development of a novel strip‐based lateral flow assay (LFA) using lanthanide‐doped upconversion nanoparticles conjugated to antibodies targeting two different biomarkers for detection of preeclampsia. We first measured circulating plasma FKBPL and CD44 protein concentrations from individuals with early‐onset preeclampsia (EOPE), using ELISA. We confirmed that the CD44/FKBPL ratio is reduced in EOPE with a good diagnostic potential. Using our rapid LFA prototypes, we achieved an improved lower limit of detection: 10 pg ml−1 for FKBPL and 15 pg ml−1 for CD44, which is more than one order lower than the standard ELISA method. Using clinical samples, a cut‐off value of 1.24 for CD44/FKBPL ratio provided positive predictive value of 100 % and the negative predictive value of 91 %. Our LFA shows promise as a rapid and highly sensitive point‐of‐care test for preeclampsia. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis, characterization and utilization of 99mTc-labelled polyethylenimine-entrapped gold nanoparticles (99mTc-Au-PENPs) for dual mode single-photon emission computed tomography/computed tomography (SPECT/CT) imaging applications. Polyethylenimine (PEI) was selected as a platform to conjugate with diethylene triamine pentacetate acid (DTPA) and polyethylene glycol monomethyl ether to synthesize Au PENPs, followed by acetylation or hydroxylation modification of the remaining PEI surface amine groups and radiolabelling of 99mTc. The generated multifunctional 99mTc-Au-PENPs with different surface groups (acetyl or hydroxyl) were characterized via different methods. The Au PENPs before 99mTc labelling are colloidally stable, haemocompatibility and noncytotoxic at an Au concentration up to 100 μM. The 99mTc-labelled Au PENPs exhibit high radiochemical purity, good stability and SPECT/CT imaging performance of different organs and lymph node. The designed strategy to use the radionuclide labelling technique and PEI-facilitated versatile nanoplatform may be extended to develop various novel nanoprobes for precision imaging applications. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis, characterization and utilization of 99mTc-labelled polyethylenimine-entrapped gold nanoparticles (99mTc-Au-PENPs) for dual mode single-photon emission computed tomography/computed tomography (SPECT/CT) imaging applications. Polyethylenimine (PEI) was selected as a platform to conjugate with diethylene triamine pentacetate acid (DTPA) and polyethylene glycol monomethyl ether to synthesize Au PENPs, followed by acetylation or hydroxylation modification of the remaining PEI surface amine groups and radiolabelling of 99mTc. The generated multifunctional 99mTc-Au-PENPs with different surface groups (acetyl or hydroxyl) were characterized via different methods. The Au PENPs before 99mTc labelling are colloidally stable, haemocompatibility and noncytotoxic at an Au concentration up to 100 μM. The 99mTc-labelled Au PENPs exhibit high radiochemical purity, good stability and SPECT/CT imaging performance of different organs and lymph node. The designed strategy to use the radionuclide labelling technique and PEI-facilitated versatile nanoplatform may be extended to develop various novel nanoprobes for precision imaging applications. [ABSTRACT FROM AUTHOR]

Utilizing dynamic cross-relaxation energy transfer in upconversion nanoparticles, they successfully predict the ideal excitation power to optimize depletion efficiency, overcoming the limitations of low-power imaging. B Super-Resolution Imaging b In article number 2205990, Yongtao Liu, Jiajia Zhou, Dayong Jin, and co-workers propose a method for improving imaging quality of upconverting stimulated emission depletion microscopy. [Extracted from the article]

We report here the fabrication, characterization and use of poly(lactic-co-glycolic acid) (PLGA) hollow microcapsules (HMs) loaded with the anticancer drug doxorubicin (DOX) for targeted drug delivery to cancer cells. In this study, PLGA HMs loaded with DOX (PLGA–DOX HMs) were prepared by a double emulsion method, followed by electrostatic assembly of positively charged polyethyleneimine (PEI) pre-modified with polyethylene glycol–folic acid segments (PEI–PEG–FA). The formed multifunctional PLGA–DOX–PEI–PEG–FA HMs were characterized via different techniques. We show that the HMs having a size of 2.5 μm are stable, and are able to release DOX in a sustained manner with a higher release rate under acidic pH conditions than that under the physiological pH conditions. Importantly, the PLGA–DOX–PEI–PEG–FA HMs displayed an effective therapeutic efficacy, comparable to that of free DOX, and were able to target cancer cells overexpressing high-affinity folic acid receptors and effectively inhibit the growth of the cancer cells. The fabricated PLGA–DOX–PEI–PEG–FA HMs may hold great promise to be used as a versatile carrier system for targeted drug delivery to different types of cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: Heparin is widely used as an anticoagulant/antithrombotic agent during clinical procedures. Overdosing of heparin can induce significant detrimental effects, such as hemorrhages and thrombocytopenia; therefore, measurement of heparin level in serum during therapy period or within infusion solutions is of vital importance. In this work, we demonstrate a green synthesis of polyethyleneimine (PEI)-stabilized gold nanoparticles (PEI/AuNPs) for highly selective and sensitive colorimetric sensing of heparin. By simply mixing PEI and Au salt in aqueous solution at room temperature, AuNPs with a mean diameter of 4.4nm can be easily formed. The formed positively charged PEI/AuNPs are able to interact with the negatively charged heparin via electrostatic interaction, resulting in the aggregation of AuNPs accompanied by a color change from wine red to light blue in solution. The color change reflected by the variation of the relevant spectroscopic features of AuNPs allows us to establish a simple, visual, and quantitative approach for colorimetric sensing of heparin. We show that the prepared PEI/AuNPs are able to detect the concentration of heparin within a range of 3–11μg/mL, and the method has a high sensitivity with a heparin detection limit of 1.5μg/mL and excellent selectivity in the presence of other biopolymers and small molecules. [Copyright &y& Elsevier]

Abstract: We report the synthesis, characterization, and utilization of gadolium-loaded dendrimer-entrapped gold nanoparticles (Gd–Au DENPs) for dual mode computed tomography (CT)/magnetic resonance (MR) imaging applications. In this study, amine-terminated generation five poly(amidoamine) dendrimers (G5.NH2) modified with gadolinium (Gd) chelator and polyethylene glycol (PEG) monomethyl ether were used as templates to synthesize gold nanoparticles (AuNPs). Followed by sequential chelation of Gd(III) and acetylation of the remaining dendrimer terminal amine groups, multifunctional Gd–Au DENPs were formed. The formed Gd–Au DENPs were characterized via different techniques. We show that the formed Gd–Au DENPs are colloidally stable and non-cytotoxic at an Au concentration up to 50 μm. With the coexistence of two radiodense imaging elements of AuNPs and Gd(III) within one NP system, the formed Gd–Au DENPs display both r 1 relaxivity for MR imaging mode and X-ray attenuation property for CT imaging mode, which enables CT/MR dual mode imaging of the heart, liver, kidney, and bladder of rat or mouse within a time frame of 45 min. Furthermore, in vivo biodistribution studies reveal that the Gd–Au DENPs have an extended blood circulation time and can be cleared from the major organs within 24 h. The strategy to use facile dendrimer technology to design dual mode contrast agents may be extended to prepare multifunctional platforms for targeted multimode molecular imaging of various biological systems. [Copyright &y& Elsevier]

• Photophysical and optical properties of organic dye and lanthanide materials. • Identify the advantage of organic dye and lanthanide hybrid nanomaterials. • Typical energy transfer mechanisms between organic dyes and lanthanide materials. • The optical properties of four types of dye-lanthanide hybrid nanomaterials. • Biomedical applications of dye-lanthanide hybrid nanomaterials. Coordination chemistry has been widely studied in lanthanide complexes, where organic ligands are used to chelate individual lanthanide ions, and the complexes are broadly used in analytical, biological, and clinical applications. Significant progress has recently been made to exploit the hybrid structure of lanthanide doped inorganic nanoparticles "coated" with organic dyes. This attributes to the fast developments of nanoscience and technology centred around well-controlled nanocrystal synthesis and engineering, with a variety of shape, size, composition and structures towards the desirable functions. There are a lot of similarities between the two forms of lanthanide materials, waiting for a systematic analysis to guide the emerging field of nanocrystal-dye hybrids. Therefore, we survey here the principles for the design of dye-lanthanide energy transfer systems and analyse the remarkable successes made in hybrid dye-lanthanide nanosystems. [ABSTRACT FROM AUTHOR]

We report a facile approach of using DNA molecules as switches to selectively activate silica coating onto specific facets of upconversion nanoparticles. Being simple and reproducible, this method improves the understanding of the silica coating mechanism and opens up new opportunities for nanomedicine delivery. [ABSTRACT FROM AUTHOR]

As a result of errors during figure assembly, incorrect data is displayed in the following panels: Figure 6C PPI (G4) with CHO, both images; Figure 6C GA-PPI-4 with CHO, both images; Figure 6C PPI(G4) with HepG2, both images; Figure 6C GA-PPI-5 with HepG2, upper image; Figure S8A 24 h after gene transfection image; Figure S10 PPI(G4) N/P 10, left image; Figure S10 GA-PPI-4 N/P 10, left image. The corrected Figure 6C, Figure S8A and Figure S10 appear below, as Figure 1, 2, and 3. [Extracted from the article]

The facile hydrothermal synthesis of polyethyleneimine (PEI)-coated iron oxide (Fe3O4) nanoparticles (NPs) doped with Gd(OH)3 (Fe3O4-Gd(OH)3-PEI NPs) for dual mode T1- and T2-weighted magnetic resonance (MR) imaging applications is reported. In this approach, Fe3O4-Gd(OH)3-PEI NPs are synthesized via a hydrothermal method in the presence of branched PEI and Gd(III) ions. The PEI coating onto the particle surfaces enables further modification of poly(ethylene glycol) (PEG) in order to render the particles with good water dispersibility and improved biocompatibility. The formed Fe3O4-Gd(OH)3-PEI-PEG NPs have a Gd/Fe molar ratio of 0.25:1 and a mean particle size of 14.4 nm and display a relatively high r2 (151.37 × 10−3 m−1 s−1) and r1 (5.63 × 10−3 m−1 s−1) relaxivity, affording their uses as a unique contrast agent for T1- and T2-weighted MR imaging of rat livers after mesenteric vein injection of the particles and the mouse liver after intravenous injection of the particles, respectively. The developed Fe3O4-Gd(OH)3-PEI-PEG NPs may hold great promise to be used as a contrast agent for dual mode T1- and T2-weighted self-confirmation MR imaging of different biological systems. [ABSTRACT FROM AUTHOR]

Development of novel drug carriers for targeted cancer therapy with high efficiency and specificity is of paramount importance and has been one of the major topics in current nanomedicine. Here we report a general approach to using multifunctional multiwalled carbon nanotubes (MWCNTs) as a platform to encapsulate an anticancer drug doxorubicin (DOX) for targeted cancer therapy. In this approach, polyethyleneimine (PEI)-modified MWCNTs were covalently conjugated with fluorescein isothiocyanate (FI) and hyaluronic acid (HA). The formed MWCNT/PEI–FI–HA conjugates were characterized via different techniques and were used as a new carrier system to encapsulate the anticancer drug doxorubicin for targeted delivery to cancer cells overexpressing CD44 receptors. We show that the formed MWCNT/PEI–FI–HA/DOX complexes with a drug loading percentage of 72% are water soluble and stable. In vitro release studies show that the drug release rate under an acidic condition (pH 5.8, tumor cell microenvironment) is higher than that under physiological condition (pH 7.4). Cell viability assay demonstrates that the carrier material has good biocompatibility in the tested concentration range, and the MWCNT/PEI–FI–HA/DOX complexes can specifically target cancer cells overexpressing CD44 receptors and exert growth inhibition effect to the cancer cells. The developed HA-modified MWCNTs hold a great promise to be used as an efficient anticancer drug carrier for tumor-targeted chemotherapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photophysical properties of lanthanide materials. • Magnetic regulation mechanisms of lanthanide luminescence. • Strategies of structure design for the hybrid magnetooptic nanosystems. • Broad applications of hybrid magnetooptic nanosystems in the multidisciplinary fields. The unique optical properties of lanthanide-doped nanomaterials have made them broadly attractive to a wide range of applications in chemical, physical, and biomedical fields. As an external and real-time regulation tool, the magnetic field is highly useful for modulating the luminescence of lanthanide ions by spectral splitting, wavelength shifting, and intensity variation. The dynamic regulation of the luminescence further endows the nanosystems with many valuable optical features, extending their versatility. Here, we analyze the magnetic regulation mechanisms of luminescence, survey the structure design of magnetooptic nanosystems, highlight their advances in imaging agents, responsive probes, nanomagnets and nanogenerators, microrobots, and miniature reactors; we also identify the challenges and future opportunities for hybrid magnetooptic nanosystems. [ABSTRACT FROM AUTHOR]

Abstract: Development of multifunctional theranostic nanoplatforms for targeted cancer imaging and therapy still remains a great challenge. Herein, we report the use of multifunctional dendrimer-entrapped gold nanoparticles (Au DENPs) covalently linked with α-tocopheryl succinate (α-TOS) as a platform for targeted cancer computed tomography (CT) imaging and therapy. In this study, amine-terminated poly(amidoamine) dendrimers of generation 5 (G5.NH2) conjugated with fluorescein isothiocyanate (FI), polyethylene glycol (PEG)-modified α-TOS, and PEGylated folic acid (FA) were used as templates to synthesize Au DENPs, followed by acetylation of the remaining dendrimer terminal amines. The formed multifunctional Au DENPs were characterized via different techniques. We show that the Au DENPs conjugated with approximately 9.8 α-TOS molecules per dendrimer and with an Au core size of 3.3 nm are water-dispersible, and stable under different pH and temperature conditions and in different aqueous media. The FA modification onto the Au DENPs enables efficient targeting of the particles to cancer cells overexpressing FA receptors (FAR), and effective targeted CT imaging of the cancer cells in vitro and the xenografted tumor model in vivo. Likewise, the covalent conjugation of α-TOS does not compromise its therapeutic activity, instead significantly improves its water solubility. Importantly, thanks to the role of FA-directed targeting, the formed multifunctional Au DENPs are able to exert the specific therapeutic efficacy of α-TOS to the FAR-overexpressing cancer cells in vitro and the xenografted tumor model in vivo. The developed multifunctional Au DENPs may hold a great promise to be used as a unique theranostic nanoplatform for targeted CT imaging and therapy of different types of cancer. [Copyright &y& Elsevier]

Removal of hazardous metal ions from industrial wastewater is of paramount importance. Taking advantage of the metal–ligand binding specificity and electrospun nanofibers with a high surface area to volume ratio and a porous structure, we developed thymine (T)-grafted poly(vinyl alcohol) (PVA)–polyethyleneimine (PEI) nanofibers for selective removal of mercury ions (Hg2+) with high efficiency. In this study, thymine-1-acetic acid was first grafted with the primary surface amines of branched PEI via a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide coupling reaction. The formed PEI–T conjugate was mixed with PVA solution for subsequent formation of T-grafted electrospun PVA–PEI (PVA–PEI-T) nanofibers. The formed PEI–T conjugate and the crosslinked PVA–PEI-T nanofibers were characterized via different techniques. We show that the grafting of the T moieties onto the surface of PEI does not appreciably impact the smooth fibrous morphology of PVA–PEI-T nanofibers when compared with the PVA–PEI nanofibers without T grafting, except that the T-grafted fibers have slightly increased fiber diameter. With the grafting of T moieties, the formed PVA–PEI-T nanofibers enabled selective removal of Hg2+ from aqueous solution and improved removal efficiency was able to be achieved by increase of the T-grafting density on the PEI surface. With the good reusability for repetitive Hg2+ removal, the newly developed T-functionalized PVA–PEI nanofibers may hold a great promise for high-selectivity and high-efficiency removal of Hg2+ from laboratory and industrial wastes. [ABSTRACT FROM AUTHOR]

Abstract: We report the synthesis and characterization of folic acid (FA)-modified multifunctional dendrimer-entrapped gold nanoparticles (Au DENPs) loaded with gadolinium (Gd) for targeted dual mode computed tomography (CT)/magnetic resonance (MR) imaging of tumors. In this work, amine-terminated generation 5 poly(amidoamine) dendrimers (G5.NH2) modified with Gd(III) chelator, polyethylene glycol (PEG) monomethyl ether, and PEGylated FA were used as templates to entrap gold nanoparticles (AuNPs). Further chelation of Gd(III) ions and acetylation of the remaining dendrimer terminal amines led to the formation of multifunctional FA-targeted Au DENPs loaded with Gd(III) (Gd–Au DENPs-FA). The formed Gd–Au DENPs-FA probes were characterized via different techniques. We show that the Gd–Au DENPs-FA probes with an Au NP core size of 4.0 nm are water dispersible, stable under different pH and temperature conditions, and cytocompatible in the given concentration range. With the co-existence of AuNPs and Gd(III) ions within the single multifunctional particles, Gd–Au DENPs-FA displayed high X-ray attenuation intensity and reasonable r 1 relaxivity. These properties of the particles enabled them to be used as dual mode nanoprobes for targeted CT/MR imaging of cancer cells in vitro and xenograft tumor model in vivo via FA receptor-mediated active targeting pathway. The strategy to design multifunctional nanoprobes using the versatile dendrimer nanotechnology may be extended to design various dual mode or multimode imaging agents for accurate diagnosis of different types of cancer. [Copyright &y& Elsevier]

We report a facile approach to fabricating low-generation poly(amidoamine) (PAMAM) dendrimer-stabilized gold nanoparticles (Au DSNPs) functionalized with folic acid (FA) for in vitro and in vivo targeted computed tomography (CT) imaging of cancer cells. In this study, amine-terminated generation 2 PAMAM dendrimers were employed as stabilizers to form Au DSNPs without additional reducing agents. The formed Au DSNPs with an Au core size of 5.5 nm were covalently modified with the targeting ligand FA, followed by acetylation of the remaining dendrimer terminal amines to endow the particles with targeting specificity and improved biocompatibility. Our characterization data show that the formed FA-modified Au DSNPs are stable at different pH values (5-8) and temperatures (4-50 °C), as well as in different aqueous media. MTT assay data along with cell morphology observations reveal that the FA-modified Au DSNPs are noncytotoxic in the particle concentration range of 0-3000 n M. X-ray attenuation coefficient measurements show that the CT value of FA-modified Au DSNPs is much higher than that of Omnipaque (a clinically used CT contrast agent) at the same concentration of the radiodense elements (Au or iodine). Importantly, the FA-modified Au DSNPs are able to specifically target a model cancer cell line (KB cells, a human epithelial carcinoma cell line) over-expressing FA receptors and they enable targeted CT imaging of the cancer cells in vitro and the xenografted tumor model in vivo after intravenous administration of the particles. With the simple synthesis approach, easy modification, good cytocompatibility, and high X-ray attenuation coefficient, the FA-modified low-generation Au DSNPs could be used as promising contrast agents for targeted CT imaging of different tumors over-expressing FA receptors. [ABSTRACT FROM AUTHOR]

Abstract: We report a facile approach to fabricating electrospun drug-loaded organic/inorganic hybrid nanofibrous system for antibacterial applications. In this study, nano-hydroxyapatite (n-HA) particles loaded with a model drug, amoxicillin (AMX) were dispersed into poly(lactic-co-glycolic acid) (PLGA) solution to form electrospun hybrid nanofibers. The loading of AMX onto n-HA surfaces (AMX/n-HA) and the formation of AMX/n-HA/PLGA composite nanofibers were characterized using different techniques. We show that AMX can be successfully adsorbed onto the n-HA surface and the formed AMX/n-HA/PLGA composite nanofibers have a uniform and smooth morphology with improved mechanical durability. Cell viability assay and cell morphology observation reveal that the formed AMX/n-HA/PLGA composite nanofibers are cytocompatible. Importantly, the loaded AMX within the n-HA/PLGA hybrid nanofibers shows a sustained release profile and a non-compromised activity to inhibit the growth of a model bacterium, Staphylococcus aureus. With the significantly reduced burst-release profile, good cytocompatibility, improved mechanical durability, as well as the remained antibacterial activity, the developed AMX/n-HA/PLGA composite nanofibers should find various potential applications in the fields of tissue engineering and pharmaceutical science. [Copyright &y& Elsevier]

The article titled "Retraction Note: One-step Conjugation of Glycyrrhetinic Acid to Cationic Polymers for High-performance Gene Delivery to Cultured Liver Cell" has been retracted by the editors of Scientific Reports. The authors of the study were unable to provide the original data for some of the experiments, leading to concerns about the reliability of the data and the conclusions of the study. All authors agree with the retraction. [Extracted from the article]

In recent years, fluorescent probes and their imaging techniques have been widely applied in environmental, biological and medical diagnostic fields. Compared with conventional fluorescent probes, luminescence nanoprobes in the second near-infrared (NIR-II) region are of importance because of their high spatial resolution, deep penetration capability, low invasiveness and autofluorescence. Among the various NIR-II nanoprobes, lanthanide-based NIR-II luminescent sensors exhibit unique advantages, such as narrow emission peaks, large Stokes shifts, longer lifetime and higher photostability. We focus on the recent progress on responsive NIR-II lanthanide nanoprobes in this review. We generalize the design strategies and synthesis methods of lanthanide nanoparticles for luminescent nanoprobe development. Then, we summarize the responsive mechanism of NIR-II lanthanide-based nanoprobes and their applications in biological systems. Finally, the challenges and future developments are discussed. • The synthetic strategy and functionalized modification for NIR-II LnNPs are summarized. • The responsive NIR-II LnNP-based nanoprobes are powerful tools for biosensing and bioimaging. • The target-activatable nanoprobes based on NIR-II LnNPs show great potential in biomedical and (pre)clinical investigations. [ABSTRACT FROM AUTHOR]

Diabetes-induced cell dysfunction of the retinal pigment epithelium (RPE) contributes to the initiation and progression of diabetic retinopathy (DR). Thioredoxin 1 (Trx1) plays a key role in DR. However, the effect and mechanism of Trx1 on diabetes-induced cell dysfunction of the RPE is not fully understood during DR. In the present study, the effect of Trx1 on this process and its related mechanism were investigated. A Trx1 overexpression cell line, ARPE19-Trx1/LacZ, was constructed and treated with or without high glucose (HG). Flow cytometry was used to analyze apoptosis of these cells and the mitochondrial membrane potential was analyzed using JC-1 staining solution. A DCFH-DA probe was also used to detect the reactive oxygen species (ROS) generation. Western blotting was used to examine the expression of related proteins in ARPE-19 cells after HG treatment. The results demonstrated that the RPE layer was damaged in clinical samples. ROS formation and RPE cell dysfunction increased after HG treatment in vitro. Besides, the expression of mitochondrial-mediated apoptosis related proteins (Bax, apoptosis-inducing factor, cytochrome C, Caspase3 and Caspase9) also increased; however, overexpression of Trx1 attenuated these changes and improved the function of ARPE19 cells. These results indicated that overexpression of Trx1 alleviated diabetes-induced RPE cell dysfunction in DR by attenuating oxidative stress. [ABSTRACT FROM AUTHOR]

Gene therapies represent a promising therapeutic route for liver cancers, but major challenges remain in the design of safe and efficient gene-targeting delivery systems. For example, cationic polymers show good transfection efficiency as gene carriers, but are hindered by cytotoxicity and non-specific targeting. Here we report a versatile method of one-step conjugation of glycyrrhetinic acid (GA) to reduce cytotoxicity and improve the cultured liver cell -targeting capability of cationic polymers. We have explored a series of cationic polymer derivatives by coupling different ratios of GA to polypropylenimine (PPI) dendrimer. These new gene carriers (GA-PPI dendrimer) were systematically characterized by UV-vis,1H NMR titration, electron microscopy, zeta potential, dynamic light-scattering, gel electrophoresis, confocal microscopy and flow cytometry. We demonstrate that GA-PPI dendrimers can efficiently load and protect pDNA, via formation of nanostructured GA-PPI/pDNA polyplexes. With optimal GA substitution degree (6.31%), GA-PPI dendrimers deliver higher liver cell transfection efficiency (43.5% vs 22.3%) and lower cytotoxicity (94.3% vs 62.5%, cell viability) than the commercial bench-mark DNA carrier bPEI (25kDa) with cultured liver model cells (HepG2). There results suggest that our new GA-PPI dendrimer are a promising candidate gene carrier for targeted liver cancer therapy. [ABSTRACT FROM AUTHOR]

Polyethyleneimine‐coated iron oxide nanoparticles doped with Gd(OH)3 are hydrothermally synthesized and modified with poly(ethylene glycol) to have good water dispersibility and biocompatibility. The formed particles with a mean particle size of 14.4 nm display relatively high r2 and r1 relaxivity, affording their use as a unique contrast agent for dual‐mode T1‐ and T2‐weighted self‐confirmation MR imaging applications, as described by G. Zhang, X. Shi, M. Shen and co‐workers on page 934. [ABSTRACT FROM AUTHOR]